At HD ranges, and with a reasonable choke, a hi brass 6 will do some damage. At HD ranges it'll still be a slug.
My house has an open floor plan. It's conceivable that I could be attempting shots of more than 15 yards. At 15 yards, bird shot out of an 18.5" barrel with no choke is not a slug. As I've said a couple times, I've hit pheasants at similar distances, watched their feathers fly and then watched them wing their way toward the horizon.
If your in-home distances are less than 12 feet (like those in the Box O Truth) tests, you might successfully defend yourself with bird shot. Then again ... you might not. Ultimately, you get to make your choice and I get to make mine.